s1 = {1, 2, 3, 4}
s2 = {3, 4, 5, 6}
#
# print(s1 & s2)
#
# print(s1 - s2)
#
# print(s2-s1)
# print(s1 | s2)
# print(s1.intersection(s2))
print(s1.difference(s2))